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Experimental Observation of Near-Field Deterioration Induced by Stimulated Rotational Raman Scattering in Long Air Paths

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Chinese Physics Letters 2011年第6期28卷 137-140页

作者： WANG Jing ZHANG Xiao-Min HAN Wei li Fu-Quan zhou li-dan FENG Bin XIANG Yong Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900

We report the experimental investigation of a stimulated rotational Raman scattering effect in long air paths on SG-III TIL,with a 1053 nm,20-cm-diameter,linearly polarized,3 ns flat-topped laser *** intense speckle pattern of near field with thickly dotted hot spots is observed at the end of propagation with an intensity-length product above 17 TW/*** Stokes developing from the scattering of the laser beam by quantum fluctuations is characterized by a combination of high spatial frequency *** observed speckle pattern with small-diameter hot spots results from the combination of the nonlinear Raman amplification and the linear diffraction propagation effect of the Stokes with a noise pattern arising from the spontaneous Raman scattering.A new promising suppression concept based on the special characteristic of the Stokes,called active and selective filtering of Stokes,is proposed.

关键词： speckle filtering intense

Temporal,Spectral and Spatial Characterization of High-Energy Laser Pulse with Small Bandwidth Propagating through Long Path

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Chinese Physics Letters 2012年第12期29卷 112-115页

作者： DENG Xue-Wei WANG Fang JIA Huai-Ting XIANG Yong FENG Bin li Ke-Yu zhou li-dan Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900

Temporal,spectral and spatial characters of 0.3-nm-bandwidth high-energy laser pulse propagating through a long path are studied in detail in one newly constructed beamline of our laser *** evolution of propagation,pulse energy and near-field deterioration are analyzed theoretically and *** argon for air is demonstrated effectively to suppress stimulated rotational Raman scattering and the experimental result provides operating criterion,and engineering parameters for the under-constructed beamlines.

关键词： scattering Small Spatial

Spin freezing induced giant exchange bias in a doped Hund's metal

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 167-174页

作者： Shunjiao li dan Zhao Jian li Baolei Kang Min Shan Yanbing zhou Xuyang li Tao Wu Xianhui Chen Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Exchange bias(EB)is a fundamental phenomenon in widespread information ***,a comprehensive understanding of its microscopic origin remains a great *** key issue in the debate is the role of frustration and disorder in the EB mechanism,which motivates the exploration of the EB effect in spin glass(SG)***,in the SG state of Crdoped Hund's metal CsFe_(2)As_(2),we discover a giant EB effect with a maximum bias field of -2 T,which is almost two orders of magnitude larger than that of traditional alloy *** results indicate that the giant EB effect should originate from the exchange interactions at the natural boundaries between the tunable ferromagnetic-like(FM)regions around Cr dopants and the SG matrix,via which the FM spins are strongly pinned by the frozen spins in the SG *** addition,the temperaturedependent and cooling-field-dependent EB behaviors could be interpreted well by the SG model with frustrated FM/SG boundaries,which provides an intuitive and explicit understanding of the impact of glassy parameters on the EB *** these results suggest that the correlated metals are promising directions for exploring the EB effect in the SG state.

关键词： Hund's metal spin glass exchange bias iron-based superconductor

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MP-MMC驱动六相永磁风力发电机建模及控制研究

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电机与控制学报 2019年第5期23卷 84-92页

作者：周荔丹李杏姚钢梅柏杉上海电力学院电气工程学院上海200090 上海交通大学电子信息与电气工程学院上海200240

针对多相模块化多电平变流器(MP-MMC)驱动多相发电机的控制问题,基于矢量空间解耦理论,建立Y移30°六相永磁同步发电机(PMSG)在旋转坐标下的数学模型;将传统三相MMC拓扑结构推广至六相,并驱动六相永磁风力发电机。在控制上采用电流矢量... 详细信息

针对多相模块化多电平变流器(MP-MMC)驱动多相发电机的控制问题,基于矢量空间解耦理论,建立Y移30°六相永磁同步发电机(PMSG)在旋转坐标下的数学模型;将传统三相MMC拓扑结构推广至六相,并驱动六相永磁风力发电机。在控制上采用电流矢量解耦方法对六相永磁风力发电机的输出电流进行跟踪,同时对系统谐波成分加以抑制;对于MMC内部子模块电容电压稳定、环流抑制,采用闭环均压策略进行控制。最后通过在软件中搭建仿真模型,对发电机稳态运行以及功率突变时运行状态进行模拟,仿真结果表明:该系统具有良好的输出特性和鲁棒性能,验证了MP-MMC能够有效驱动六相永磁发电机实现平稳发电。

关键词：六相永磁同步发电机模块化多电平变流器矢量空间解耦矢量控制闭环均压控制

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煤化工酸性气脱硫技术的对比分析研究

化学工程 2017年第7期45卷 69-73页

作者：周丹黎张翔华陆工程科技有限责任公司陕西西安710065

简述了煤化工酸性气脱硫现状,重点阐述了克劳斯及其络合铁法脱硫联合技术、克劳斯加氨法脱硫技术和克劳斯加碱法脱硫技术的工艺流程、反应原理和技术特点,分析比较3种技术脱硫的优缺点。通过对3种技术的适用性分析研究,得出克劳斯及其... 详细信息

简述了煤化工酸性气脱硫现状,重点阐述了克劳斯及其络合铁法脱硫联合技术、克劳斯加氨法脱硫技术和克劳斯加碱法脱硫技术的工艺流程、反应原理和技术特点,分析比较3种技术脱硫的优缺点。通过对3种技术的适用性分析研究,得出克劳斯及其络合铁法脱硫联合技术更适合在煤化工酸性含硫、含氨气体治理中应用的结论。

关键词：克劳斯及其络合铁联合技术克劳斯加氨法克劳斯加碱法煤化工酸性气适用性分析

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong li li dan Jing Peng Qidong Yang Fuqiang Yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

Deciphering the mechanism of structural transformation between Pd3L6 and Pd4L8 metal-organic cages

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Science China Chemistry 2025年

作者： Xian-Chao zhou Yong-Zhen Tan Ying-Ying Ge Ya-liang Lai Dong Luo Xiao-Ping zhou dan li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University

Metal-organic cages can undergo structural transformations due to the dynamic nature of dative bonds,however,the mechanism of transformation processes is often *** we report four metal-organic cages featuring Pd3L6-type and Pd4L8-type tubular structures by self-assembly of Pd（II） and two types of bidentate *** Pd3L6-type MOCs were synthesized in H2O while the Pd4L8-type cages were formed in dimethyl sulfoxide （DMSO）,indicating the solvent is critical for the *** structure transformation between Pd3L6and Pd4L8metal-organic cages can be interconverted when switching the DMSO and H2O in a relatively high *** cages partly disassemble into the metalloligands and Pd2+ions due to the competitive coordination of DMSO/H2O at low concentrations,achieving a concentration-controlled transformation ***,the structure transformation was monitored by ESI-MS,and the species of intermediate were detected,which provided direct clues for deciphering the mechanism of structural transformation.

关键词：

基于IGBT的±10kvar STATCOM装置设计

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电力自动化设备 2006年第5期26卷 61-65页

作者：陶礼学姚钢周荔丹陈陈上海交通大学电子信息与电气工程学院上海200030

静止同步补偿器(STATCOM)是目前用于电力系统无功补偿的装置。介绍了基于绝缘栅双极晶体管(IGBT)的±10kvarSTATCOM装置的设计方案。论述了该装置的主电路方案、结构、功率、保护措施和启动方式。装置的控制器和脉冲发生器采用双数字信... 详细信息

静止同步补偿器(STATCOM)是目前用于电力系统无功补偿的装置。介绍了基于绝缘栅双极晶体管(IGBT)的±10kvarSTATCOM装置的设计方案。论述了该装置的主电路方案、结构、功率、保护措施和启动方式。装置的控制器和脉冲发生器采用双数字信号处理器(DSP)加现场可编程门阵列(FPGA)的多CPU控制系统。动模实验结果表明,该装置电压、电流谐波畸变率≤5%;响应时间≤40ms;装置的转换效率为94.92%,满足应用需要。

关键词：静止同步补偿器 IGBT 无功补偿

Extracting ship and heading from Sentinel-2 images using convolutional neural networks with point and vector learning

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Journal of Oceanology and limnology 2025年第1期43卷 16-28页

作者： Xiunan li Peng CHEN Jingsong YANG Wentao AN dan LUO Gang ZHENG Aiying LU Ocean College Zhejiang UniversityZhoushan 316021China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China National Satellite Ocean Application Service Ministry of Natural ResourcesBeijing 100081China

Obtaining accurate ship positions and headings in remote sensing images plays a crucial role in various ***,current deep learning-based methods primarily focus on ship position detection,while the detection of ship wakes relies on traditional non-deep learning approaches,which often underperform in complex marine *** proposed a novel,simple,and efficient method called Point-Vector *** proposed method leverages convolutional neural networks(CNN)for feature extraction and subsequently integrates multi-scale features to generate high-resolution feature *** the final stage,ship positions and headings are represented using a combination of points and *** experiments with results from automatic identification system(AIS)reports demonstrate that our method achieved impressive performance in two-class ship target detection,with an average precision of 96.4%,recall rate of 94.3%,and an F 1 score of 95.2%.Notably,the average heading error was 3.3°.The proposed model achieved a practical inference speed(FPS>30),and the average processing time for inferring a large-scale Sentinel-2 remote sensing image was 11.4 s.

关键词： deep learning ship detection heading remote sensing Sentinel-2